Table 7 Definition of social interaction phenotypes

^a Affiliative - sum of bidirectional, unidirectional, and approach behavior

^a bidirectional

simultaneous display of affiliative behaviors by the subject and partner mouse (e.g. simultaneous facial sniffing, grooming, anogenital sniffing), irrespective of which mouse initiated the contact

^a unidirectional

affiliative behavior displayed by subject with no observable response from partner

^a approach

subject walks towards or follows partner (not coded if attack behavior immediately follows)

^a nonsocial

no subject-partner interaction

^a Aversive - sum of passive avoidance, active avoidance, freezing, and aggression

^a passive avoidance

partner-initiated affiliative social contact passively ignored by subject without moving away

^a active avoidance

partner-initiated affiliative social contact actively ignored by subject by moving away

^a freezing

crouched, prone, & immobile posture lasting ≥ 1.0 second

^a aggression

vigorous lunge and bite typically directed at the partners' flanks and back, but also including lunges, feints, chasing, tail-rattling, and bites without lunge.

attack

vigorous lunge and bite

attack latency

amount of time expired from beginning of the social interaction test till the first attack